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/**

* A short example showing how to reverse a string

* @flow

*/

/**

* Create a new string and append

* @complexity O(n)

*/

function ReverseStringIterative (string) {

if (typeof string !== 'string') {

throw new TypeError('The given value is not a string')

}

let reversedString = ''

let index

for (index = string.length - 1; index >= 0; index--) {

reversedString += string[index]

}

return reversedString

}

/**

* JS disallows string mutation so we're actually a bit slower.

*

* @complexity: O(n)

*

* 'some' -> 'eoms' -> 'emos'

*/

function ReverseStringIterativeInplace (string) {

if (typeof string !== 'string') {

throw new TypeError('The given value is not a string')

}

const _string = string.split('')

for (let i = 0; i < Math.floor(_string.length / 2); i++) {

const first = _string[i]

const second = _string[_string.length - 1 - i]

_string[i] = second

_string[_string.length - 1 - i] = first

}

return _string.join('')

}

export { ReverseStringIterative, ReverseStringIterativeInplace }